Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include "drawterm.h"

void*
erealloc(void *v, ulong n)
{
        v = realloc(v, n);
        if(v == nil)
                sysfatal("out of memory");
        return v;
}

char*
estrdup(char *s)
{
        s = strdup(s);
        if(s == nil)
                sysfatal("out of memory");
        return s;
}

char*
estrappend(char *s, char *fmt, ...)
{
        char *t;
        va_list arg;

        va_start(arg, fmt);
        t = vsmprint(fmt, arg);
        if(t == nil)
                sysfatal("out of memory");
        va_end(arg);
        s = erealloc(s, strlen(s)+strlen(t)+1);
        strcat(s, t);
        free(t);
        return s;
}

/*
 *  prompt for a string with a possible default response
 */
char*
readcons(char *prompt, char *def, int raw)
{
        int fdin, fdout, ctl, n;
        char line[10];
        char *s;

        fdin = open("/dev/cons", OREAD);
        if(fdin < 0)
                fdin = 0;
        fdout = open("/dev/cons", OWRITE);
        if(fdout < 0)
                fdout = 1;
        if(def != nil)
                fprint(fdout, "%s[%s]: ", prompt, def);
        else
                fprint(fdout, "%s: ", prompt);
        if(raw){
                ctl = open("/dev/consctl", OWRITE);
                if(ctl >= 0)
                        write(ctl, "rawon", 5);
        } else
                ctl = -1;
        s = estrdup("");
        for(;;){
                n = read(fdin, line, 1);
                if(n == 0){
                Error:
                        close(fdin);
                        close(fdout);
                        if(ctl >= 0)
                                close(ctl);
                        free(s);
                        return nil;
                }
                if(n < 0)
                        goto Error;
                if(line[0] == 0x7f)
                        goto Error;
                if(n == 0 || line[0] == '\n' || line[0] == '\r'){
                        if(raw){
                                write(ctl, "rawoff", 6);
                                write(fdout, "\n", 1);
                        }
                        close(ctl);
                        close(fdin);
                        close(fdout);
                        if(*s == 0 && def != nil)
                                s = estrappend(s, "%s", def);
                        return s;
                }
                if(line[0] == '\b'){
                        if(strlen(s) > 0)
                                s[strlen(s)-1] = 0;
                } else if(line[0] == 0x15) {    /* ^U: line kill */
                        if(def != nil)
                                fprint(fdout, "\n%s[%s]: ", prompt, def);
                        else
                                fprint(fdout, "\n%s: ", prompt);
                        
                        s[0] = 0;
                } else {
                        s = estrappend(s, "%c", line[0]);
                }
        }
        return nil; /* not reached */
}